utils: draft implementation for queue drop tracer
diff --git a/utils/tracers/l2-rate-tracer.h b/utils/tracers/l2-rate-tracer.h
new file mode 100644
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+++ b/utils/tracers/l2-rate-tracer.h
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+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -*- */
+/*
+ * Copyright (c) 2013 University of California, Los Angeles
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation;
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Author: Alexander Afanasyev <alexander.afanasyev@ucla.edu>
+ */
+
+#ifndef L2_RATE_TRACER_H
+#define L2_RATE_TRACER_H
+
+#include "l2-tracer.h"
+
+#include "ns3/nstime.h"
+#include "ns3/event-id.h"
+
+#include <boost/tuple/tuple.hpp>
+#include <boost/shared_ptr.hpp>
+#include <map>
+
+namespace ns3 {
+
+/**
+ * @ingroup ndn
+ */
+class L2RateTracer : public L2Tracer
+{
+public:
+ /**
+ * @brief Network layer tracer constructor
+ */
+ L2RateTracer (boost::shared_ptr<std::ostream> os, Ptr<Node> node);
+ virtual ~L2RateTracer ();
+
+ /**
+ * @brief Helper method to install tracers on all simulation nodes
+ *
+ * @param file File to which traces will be written
+ * @param averagingPeriod Defines averaging period for the rate calculation,
+ * as well as how often data will be written into the trace file (default, every half second)
+ *
+ * @returns a tuple of reference to output stream and list of tracers. !!! Attention !!! This tuple needs to be preserved
+ * for the lifetime of simulation, otherwise SEGFAULTs are inevitable
+ *
+ */
+ static boost::tuple< boost::shared_ptr<std::ostream>, std::list<Ptr<L2RateTracer> > >
+ InstallAll (const std::string &file, Time averagingPeriod = Seconds (0.5));
+
+ void
+ SetAveragingPeriod (const Time &period);
+
+ virtual void
+ PrintHeader (std::ostream &os) const;
+
+ virtual void
+ Print (std::ostream &os) const;
+
+ virtual void
+ Drop (Ptr<const Packet>);
+
+private:
+ void
+ PeriodicPrinter ();
+
+ void
+ Reset ();
+
+private:
+ boost::shared_ptr<std::ostream> m_os;
+ Time m_period;
+ EventId m_printEvent;
+
+ mutable boost::tuple<Stats, Stats, Stats, Stats> m_stats;
+};
+
+} // namespace ns3
+
+#endif // L2_RATE_TRACER_H